This view shows enzymes only for those organisms listed below, in the list of taxa known to possess the pathway. If an enzyme name is shown in bold, there is experimental evidence for this enzymatic activity.
Synonyms: IAA degradation I, IAA oxidation I, IAA turnover I, IAA catabolism I
|Superclasses:||Degradation/Utilization/Assimilation → Hormones Degradation → Plant Hormones Degradation → Auxins Degradation|
Some taxa known to possess this pathway include : Zea mays
Expected Taxonomic Range: Magnoliophyta
The plant hormone indole-3-acetic acid (IAA) can be degraded (inactivated) via either decarboxylative or non-decarboxylative oxidation. Decarboxylative oxidation involves plant peroxidase. The pathway and role of decarboxylative oxidation in IAA metabolism in higher plants are not clear. Studies in varies plants on non-decarboxylative oxidation suggest it is the major catabolic route of IAA. Different plant species however employs different initial steps in non-decarboxylative oxidation. Maize readily oxidizes free IAA whereas hybrid aspen oxidizes aspartic acid-conjugated IAA (IAA-asp). Arabidopsis, on the other hand, oxidizes both free IAA and IAA-asp. These representative pathways are curated separately in the Metacyc database.
The maize degradation pathway depicted here is based on in-vivo feeding experiments and in-vitro assay with plant extracts. Enzymes of the pathway have not been purified, nor do the genes isolated.
Variants: indole-3-acetate conjugate biosynthesis II, indole-3-acetate degradation II, indole-3-acetate degradation III, indole-3-acetate degradation IV, indole-3-acetate degradation V, indole-3-acetate degradation VI, indole-3-acetate degradation VII, indole-3-acetate degradation VIII (bacterial)
Kowalczyk: Kowalczyk, Mariusz "Metabolism and homeostasis of indole-3-acetic acid in Arabidopsis thaliana." Doctoral diss. Dept. of Forest Genetics and Plant Physiol., SLU. Acta Universitatis Agriculturae Sueciae. Silvestria Vol. 256.
Nonhebel85: Nonhebel HM, Kruse LI, Bandurski RS (1985). "Indole-3-acetic acid catabolism in Zea mays seedlings. Metabolic conversion of oxindole-3-acetic acid to 7-hydroxy-2-oxindole-3-acetic acid 7'-O-beta-D-glucopyranoside." J Biol Chem 260(23);12685-9. PMID: 4044604
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